Hepatocellular Carcinoma in Sheep.

This tumor is uncommon but found in ox, sheep and dog and less commonly in the cat, pig and horse. in great britain hepatocellular carcinoma (hcc) comprises 20 percent of all tumors found inslaughtered sheep, affected animals are usually adult, though hepatoma has been found even in newborn lambs, this tumor appeared to be congenital origin but mostly described in older lambs (molton 1978, cotchin 1984). the incidence for this tumor is usually between 4 and 8 years in cows arid over one year (often 4-5 years) in sheep (molton 1978). in a 12 month surveys of neoplasm found in 100 abattoirsthroughout great britain in sheep 32 of 107 tumors originated in the liver, 8 of these tumors were found in younger than one and 24 in older than one year sheep (anderson & sandison 1968). the study of sheep hepatocellular carcinoma in india 2 of 408 livers from sheep aged 4-5 years showed changes associated with hepatoma (krishna et at 1973). in iran one case of hepatocellular carcinoma in a cow and cholangiocellur carcinoma in a sheep were reported (gholami & ezzi 2000). hepatocellular carcinoma is one of the most common carcinoma in man (damjanov & linder 1996, robbins et at 1984).